import 'package:flutter/material.dart';
enum SearchBarType {home, normal, homeLight}
class SearchBar extends StatefulWidget {
  final bool enabled;
  final bool hideLeft;
  final SearchBarType searchBarType;
  final String hint;
  final String defaultText;
  final void Function() leftButtonClick;
  final void Function() rightButtonClick;
  final void Function() speakClick;
  final void Function() inputBoxClick;
  final ValueChanged<String> onChanged;

  SearchBar({
    this.enabled = true,
    this.hideLeft,
    this.searchBarType = SearchBarType.normal,
    this.hint,
    this.defaultText,
    this.leftButtonClick,
    this.rightButtonClick,
    this.speakClick,
    this.inputBoxClick,
    this.onChanged
  });

  @override
  _SearchBarState createState() => _SearchBarState();

}

class _SearchBarState extends State<SearchBar> {
  bool showClear = false;
  final TextEditingController _controller = TextEditingController();
  @override
  void initState() {
    if (widget.defaultText != null) {
      setState(() {
        _controller.text = widget.defaultText;
      });
    }
    super.initState();
  }
  @override
  Widget build(BuildContext context) {
    return widget.searchBarType == SearchBarType.normal ? _genNormalSearch() : _genHomeSearch();
  }

  _genNormalSearch() {
    return Container(
      padding: EdgeInsets.fromLTRB(6, 5, 10, 5),
      child: Row(
        children: [
          _wrapTap(
            Container(
              child: widget.hideLeft?null:Icon(Icons.arrow_back_ios, color: Colors.grey, size: 26,),
            ),
            widget.leftButtonClick
          ),
          Expanded(
            flex: 1,
            child: _inputBox(),
          ),
          _wrapTap(
              Container(
                padding: EdgeInsets.fromLTRB(10, 5, 10, 5),
                child: Text(
                  '搜索',
                  style: TextStyle(color: Colors.blue, fontSize: 17),
                ),
              ),
              widget.rightButtonClick
          ),
        ],
      ),
    );
  }

  _genHomeSearch() {
    return Container(
      child: Row(
        children: [
          _wrapTap(
              Container(
                padding: EdgeInsets.fromLTRB(6, 5, 5, 5),
                child: Row(
                  children: [
                    Text(
                      '上海',
                      style: TextStyle(color: _homeFontColor(), fontSize: 14),
                    ),
                    Icon(Icons.expand_more, color: _homeFontColor(),size: 22,)
                  ],
                )
              ),
              widget.leftButtonClick
          ),
          Expanded(
            flex: 1,
            child: _inputBox(),
          ),
          _wrapTap(
              Container(
                padding: EdgeInsets.fromLTRB(10, 5, 10, 5),
                child: Icon(
                  Icons.comment, color: _homeFontColor(), size: 26,
                )
              ),
              widget.rightButtonClick
          ),
        ],
      ),
    );
  }

  _wrapTap(Widget child, void Function() callBack) {
    return GestureDetector(
      onTap: () {
        if (callBack != null) {
          callBack();
        }
      },
      child: child,
    );
  }

  _inputBox() {
    Color inputBoxColor;
    if (widget.searchBarType == SearchBarType.home) {
      inputBoxColor = Colors.white;
    } else {
      inputBoxColor = Color(int.parse('0xffEDEDED'));
    }
    return Container(
      height: 30,
      padding: EdgeInsets.fromLTRB(10, 0, 10, 0),
      decoration: BoxDecoration(
        color: inputBoxColor,
        borderRadius: BorderRadius.circular(widget.searchBarType == SearchBarType.normal ? 5 : 15)
      ),
      child: Row(
        // mainAxisAlignment: MainAxisAlignment.center,
        children: [
          Icon(Icons.search, size: 25, color: widget.searchBarType==SearchBarType.normal?Color(0xffA9A9A9):Colors.blue),
          SizedBox(width: 5),
          Expanded(
            flex: 1,
            child:
            widget.searchBarType==SearchBarType.normal?
            TextField(
              controller: _controller,
              onChanged: _onChange,
              autofocus: true,
              style: TextStyle(
                fontSize: 18.0,
                color: Colors.black,
                fontWeight: FontWeight.w300
              ),
              //输入文本样式
              decoration: InputDecoration(
                // contentPadding: EdgeInsets.only(left: 5, right: 5),
                border: InputBorder.none,
                hintText: widget.hint ?? "",
                hintStyle: TextStyle(fontSize: 15)
              ),
            ):_wrapTap(
              Container(
                child: Text(
                  widget.defaultText,
                  style: TextStyle(
                    fontSize: 13,
                    color: Colors.grey
                  ),
                ),
              ),
              widget.inputBoxClick
            )
          ),
          !showClear?
              _wrapTap(Icon(Icons.mic, size: 22, color: widget.searchBarType == SearchBarType.normal ? Colors.blue : Colors.grey,), widget.speakClick)
              : _wrapTap(Icon(Icons.clear, size: 22, color: Colors.grey,), () {
                setState(() {
                _controller.clear();
                });
              _onChange('');})
        ],
      ),
    );
  }

  _onChange(String text) {
    if (text.length > 0) {
      setState(() {
        showClear = true;
      });
    } else {
      setState(() {
        showClear = false;
      });
    }
    if (widget.onChanged != null) {
      widget.onChanged(text);
    }
  }

  _homeFontColor() {
    return widget.searchBarType  == SearchBarType.homeLight ?
        Colors.black54 : Colors.white;
  }
}

